It isn't just about the money (although it helps if invested correctly) its more about coaching.
Look at Leicester & West Ham as examples of money spent wisely and good coaching as opposed to Everton were the money is 'wasted'.
If it was only down to money, which is dictated by income (tv money, gate money, sponsorship & directors loans) which is basically dictated by the perceived size of the club, then Sunderland, Ipswich, Portsmouth & Wednesday should walk the third division.
Based on more recent Premier league history you could also add Bolton, Wigan & Charlton to that list.
I bet we finish above most of those clubs, if we get the "four extra players" in and don't loose Smith.